x86: Sync up tsc_timer with Linux

Since we are using the code from Linux, update it to the newer version
in v6.11

Signed-off-by: Simon Glass <sjg@chromium.org>

diff --git a/drivers/timer/tsc_timer.c b/drivers/timer/tsc_timer.c
index 2f2c2f27b7ff07af38c12d4780e9b486906baa09..dd16ab320b2f3324837edd33396c4552595d40c3 100644 (file)
--- a/drivers/timer/tsc_timer.c
+++ b/drivers/timer/tsc_timer.c
@@ -83,7 +83,7 @@ static unsigned long cpu_mhz_from_cpuid(void)
        if (cpuid_eax(0) < 0x16)
                return 0;
 
-       return cpuid_eax(0x16);
+       return cpuid_eax(0x15);
 }
 
 /*
@@ -299,10 +299,19 @@ static unsigned long __maybe_unused quick_pit_calibrate(void)
                        if (!pit_expect_msb(0xff-i, &delta, &d2))
                                break;
 
+                       delta -= tsc;
+
+                       /*
+                        * Extrapolate the error and fail fast if the error will
+                        * never be below 500 ppm.
+                        */
+                       if (i == 1 &&
+                           d1 + d2 >= (delta * MAX_QUICK_PIT_ITERATIONS) >> 11)
+                               return 0;
+
                        /*
                         * Iterate until the error is less than 500 ppm
                         */
-                       delta -= tsc;
                        if (d1+d2 >= delta >> 11)
                                continue;